Working in an under ventilated facility during the summer is no fun. When a buildings product company wanted to improve the environment for their employees, they turned to Eldridge to provide a solution to reduce the summer heat. In this blog, I’ll talk about the challenges that we had to overcome to design a ventilation system that best fit the customer’s needs.
Poor Ventilation System Design
The customer had one very large metal building that was a result of constructing several buildings side by side. The original ventilation system consisted of only ridge vents on the ridge of each building section. Over time, some exhaust fans had been added to the walls in each building section. In the hottest part of the building around the glass furnaces, they added some inexpensive commercial grade upblast fans.
The resulting air flow throughout the large building was not working. The wall exhaust fans were pulling in hot air coming from the metal roof through the ridge vents. Where they had installed the upblast fans, the fans were short circuiting. Their proximity to the ridge vents resulted in air pulled in through the ridge vents. There was little to no heat reduction around the glass furnaces.
Design Challenges
There were several challenges that we had to overcome to provide a solution. The first was that the customer did not want to incur the cost or inconvenience to remove the ridge vents. There were over 400 feet of ridge vents on the multiple ridges. Most of the ridge vents were located over production areas which meant a disruption to product output or more costly removal at nights and on weekends. To overcome this challenge, we incorporated the ridge vents into the ventilation system redesign as exhaust outlets and supplemented them with powered exhaust fans on the roof.
The second challenge was the uneven pavement and gravel roads that surrounded the building. That meant lifting heavy exhaust fans to the roof by crane would be risky. Some of the fans would need to be located over 200 feet from the building’s end wall.
The third challenge was that the customer didn’t want any chance of water leaking through roof mounted fans. That eliminated using our roof mounted upblast fan which are mostly reliable. However, upblast fans sometimes leak due to bad seals on the butterfly dampers or leaks along the gutter between the two damper blades.
The way we overcame design challenges two and three was to use an Eldridge flange fan, a separate mounting plate and a separate hood. Each of these three pieces were light enough that they could be carried across the roof along a purlin.
Ventilation System Solution
The goal with our ventilation system redesign was to make sure that the inside and outside temperatures were the same. To do that, we needed to remove the solar and glass furnace heat loads. Our solution utilized 31 Eldridge hooded wall supply fans to provide over 775,000 CFM of air flow and an air change rate over 6. On the exhaust side, we placed 15 Eldridge flange fans on the roof to supplement the ridge vents. The result was a slight positive pressure in the building which worked to push rising hot air out through the ridge vents and roof fans.
In the area around the glass furnaces, we doubled the air change rate. The additional air flow was sufficient to remove the heat generated by the furnaces. We placed several of the roof exhaust fans directly above them to keep the heat from spreading to other parts of the building.
The customer and the employees are very pleased with the new ventilation system. On the hottest days this summer, the temperature inside the building was the same as the outside temperature. In prior summers, around the glass furnaces, they were experiencing a temperature rise of over 30 degrees F. This summer, the temperature rise has been less than 5 degrees F.
Conclusion
The Eldridge ventilation experts have the skills and experience to redesign any ventilation system. We can create a successful environment for people, products, and processes even for applications that have multiple design challenges. If you want to reduce the summer heat and create a successful environment in your facility, call us and we’ll design a ventilation system solution that works for your application.